<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      .loading {
        width: 1000px;
        height: 200px;
        background: linear-gradient(
          90deg,
          #f3f3f3 25%,
          #e9e9e9 50%,
          #f3f3f3 75%
        );
        background-size: 200% 100%;
        animation: loadingAnimation 1.5s linear infinite;
      }

      @keyframes loadingAnimation {
        0% {
          background-position: 100% 0;
        }
        100% {
          background-position: -100% 0;
        }
      }
    </style>
  </head>
  <body>
    <div class="loading"></div>
  </body>
</html>
